Conventional keyword-based search methods are limited to finding results focused on the keywords. They are generally not able to find conceptually related objects or other information related to the keywords in the query. For example, if a user needs to search for a product or service, but the user only knows a feature or function of the product or service, without knowing the name of the product or service, conventional search methods may not be able to return a satisfactory answer. For example, if the query is “What are the products that can be used to take a picture?” or simply “take pictures”, conventional search methods will face at least two challenges. One is to adequately understand the meanings of a natural language query, and the other is to find correct answers to the question. Conventional question-answering approaches require intensive manual work to build a knowledge base and have not been able to provide effective solutions for solving practical problems. More advanced and implementable technologies are needed to serve the ever-increasing information needs.